Biomarker and Safety Study of Clozapine in Patients With Benign Ethnic Neutropenia (BEN)
BEN
1 other identifier
interventional
274
1 country
1
Brief Summary
Clozapine (CLZ) is the most effective antipsychotic for treatment-refractory schizophrenia (SZ). Despite the overwhelming evidence of superior efficacy, CLZ is infrequently prescribed in the US, at a considerably lower rate than the estimated prevalence of treatment-resistant SZ, especially for African-Americans (AA). Recent evidence suggests that low Absolute Neutrophil Counts (ANC), either at baseline or during treatment are a significant barrier to CLZ use in AA patients in the US, where guidelines mandate CLZ discontinuation if ANC drops below 1500 cells/mm3. The investigators group has found that discontinuation of CLZ in AA patients is over twice that in European-American (EA) patients (N\~400; 42% vs.19%, P=0.041) and initiation rates are 50% lower. In a Statewide study (N=1875), the investigators reported that discontinuation was more frequently due to neutropenia in the AA sample, though no AA had developed agranulocytosis (8 cases in EA). Benign Ethnic Neutropenia (BEN) in people of African ancestry, including AAs, identifies a group (50% of AA) with low ANCs but no increased risk of agranulocytosis or infection. Low baseline or in-treatment fluctuations requiring CLZ discontinuation under current prescribing guidelines are common in CLZ-treated persons with BEN. In the investigators recent pilot study of N=12 AA patients with BEN, treatment was safely and successfully continued with CLZ despite low baseline ANC (outside current guidelines). Recent evidence implicates a polymorphism in the Duffy Antigen Receptor Chemokine (DARC) gene in the pathophysiology of BEN. In homozygotes (FY-/-) for the DARC null allele, mean within-subject neutrophil counts are reduced, resulting in sporadic ANC \<1500 cells/mm3 in 10-15% of people with the allele. In population studies, the FY-/- genotype is found in 0.01% of EAs, 99.3% of sub-Saharan Africans (SSA), and 68% of AAs. Further, a missense DARC mutation has been reported to interact with the DARC FY-/- in determining low WBC in AAs. Normal patterns of week-to-week fluctuation in ANC levels in individuals of African ancestry with BEN and the DARC null genotype are not known, and no published research has examined variation in ANC in African ancestry CLZ-treated SZ patients with BEN and the DARC null genotype (FY-/-). Such data are also lacking on individuals with BEN without the DARC null genotype. Conducting such research will generate genetic marker and safety data that could be used to expand access to CLZ for AA patients who otherwise are eligible to receive this superior treatment option.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable schizophrenia
Started Jul 2015
Longer than P75 for not_applicable schizophrenia
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
February 26, 2015
CompletedFirst Posted
Study publicly available on registry
March 31, 2015
CompletedStudy Start
First participant enrolled
July 1, 2015
CompletedPrimary Completion
Last participant's last visit for primary outcome
October 26, 2021
CompletedStudy Completion
Last participant's last visit for all outcomes
October 26, 2021
CompletedResults Posted
Study results publicly available
January 31, 2023
CompletedJanuary 31, 2023
January 1, 2023
6.3 years
February 26, 2015
November 2, 2022
January 11, 2023
Conditions
Outcome Measures
Primary Outcomes (2)
Change in White Blood Cell (WBC) (mm3) and Absolute Neutrophil Counts (ANC) (mm3) in Persons According to Presence of the DARC Null Allele.
24 week period baseline and endpoint
Number of Episodes of Agranulocytosis (Count).
6 months
Study Arms (1)
Clozapine
EXPERIMENTALInterventions
Eligibility Criteria
You may qualify if:
- Eligible and recommended for clozapine treatment (e.g. treatment resistant schizophrenia, schizoaffective disorder, bipolar disorder, other psychotic disorder, delusional disorder, hostility, other documented rationale)
- Male or Female
- African Ancestry (African, African-American or African-Caribbean). This population will make up the majority of the study. However, there are cases of BEN in individuals of Middle Eastern, Caucasian, and other ethnicity. The investigators will accept these patients as they may have unknown African ancestry and genotyping will be important.
- Age: 18 to 64 years.
- History of a low absolute neutrophil count (ANC\<2500 cells/mm3 in past 24 months)
- Documented ability to sign informed consent. This is a score of ≥10/12 on ESC.
- Effective birth control if of child bearing potential
You may not qualify if:
- DSM-IV diagnosis of Mental Retardation
- Pregnancy or lactation
- History of myeloproliferative disorder
- Uncontrolled seizure disorder
- History of paralytic ileus
- History of clozapine-induced ANC \< 700 mm3
- Systemic Lupus Erythematosus, Multiple Sclerosis, Hashimoto's Thyroiditis, Sjogren's Syndrome, Grave's Disease\*
- Medical condition whose pathology or treatment would likely alter the presentation or treatment of schizophrenia or significantly increase the risks associated with the proposed protocol.
- Medical condition affecting patient's ability to mount an immune response
- Current bacterial or viral infection\*
- Sickle cell anemia
- Positive for bacteria in urine culture\*
- Temperature \> 37.5 º Celsius, 99.5 º Fahrenheit\*
- Current treated or untreated cancer\*
- Documented nutritional deficiencies (such as Beriberi, Pellagra, Rickets, Scurvy, Keshan Disease)\*
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
Maryland Psychiatric Research Center
Catonsville, Maryland, 21228, United States
Related Publications (1)
Cavaliere VS, Glassman M, DiPaula BA, Mackowick M, Wehring HJ, Liu F, Chen S, Park J, Love RC, Richardson CM, Vyas G, Kearns AM, Kelly DL. Anti-aggressive effects of clozapine in involuntarily committed black patients with severe mental illness. Schizophr Res. 2022 May;243:163-169. doi: 10.1016/j.schres.2022.03.006. Epub 2022 Mar 28.
PMID: 35358857DERIVED
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Results Point of Contact
- Title
- Dr. Deanna L. Kelly, Pharm.D., BCPP
- Organization
- Maryland Psychiatric Research Center
Study Officials
- PRINCIPAL INVESTIGATOR
Deanna L Kelly, Pharm.D, BCPP
Principal Investigator
Publication Agreements
- PI is Sponsor Employee
- No
- Restrictive Agreement
- No
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- NA
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- SINGLE GROUP
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Principal Investigator
Study Record Dates
First Submitted
February 26, 2015
First Posted
March 31, 2015
Study Start
July 1, 2015
Primary Completion
October 26, 2021
Study Completion
October 26, 2021
Last Updated
January 31, 2023
Results First Posted
January 31, 2023
Record last verified: 2023-01